Problem: $-2lm - 10ln - 8l - 8 = -6m + 3$ Solve for $l$.
Solution: Combine constant terms on the right. $-2lm - 10ln - 8l - {8} = -6m + {3}$ $-2lm - 10ln - 8l = -6m + {11}$ Notice that all the terms on the left-hand side of the equation have $l$ in them. $-2{l}m - 10{l}n - 8{l} = -6m + 11$ Factor out the $l$ ${l} \cdot \left( -2m - 10n - 8 \right) = -6m + 11$ Isolate the $l$ $l \cdot \left( -{2m - 10n - 8} \right) = -6m + 11$ $l = \dfrac{ -6m + 11 }{ -{2m - 10n - 8} }$ We can simplify this by multiplying the top and bottom by $-1$. $l= \dfrac{6m - 11}{2m + 10n + 8}$